Instead of special-casing the current fields that may have
WeakSerializationReferences, handle WSRs appearing as elements
or properties of objects more generally. This removes existing
special casing and avoids the need for it in case of new
future uses of WSRs.
For artificial nodes being added for dropped
WeakSerializationReference targets, add them as kArtificial nodes
(not kSnapshot) that has the original offset (element) or
name (property). The replacement is added as a kSnapshot node
that has a negative offset with the same magnitude as the
artificial node (element) or ":real_<property name>" (property).
This simplifies the work done in pkg/vm_snapshot_analysis to
use the artificial nodes instead of replacement ones for
reassembling hierarchies and the like.
This CL also cleans up the old SerializerWritingObjectScope
class, both moving it to Serializer::WritingObjectScope and
allowing nesting of WritingObjectScopes with the correct
semantics.
Thanks to this, not only can we recur when under a WritingObjectScope
instead of lifting recursion outside of those scopes, but we can
also create artificial nodes for non-empty per-code object pools and
static call target tables instead of attributing their contents
as supposed elements of the Code object being written.
TEST=pkg/vm_snapshot_analysis/test/instruction_sizes_test
Cq-Include-Trybots: luci.dart.try:pkg-linux-release-try,pkg-mac-release-try,pkg-win-release-try
Change-Id: Ib945c5afcd89b1458b8be3559b6eae24048aba2f
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/194243
Commit-Queue: Tess Strickland <sstrickl@google.com>
Reviewed-by: Ryan Macnak <rmacnak@google.com>
Reviewed-by: Vyacheslav Egorov <vegorov@google.com>
* When looking for Code node owner simply always check for synthetic
owner (referenced through ':owner_' property) first. If it is present
then it means 'owner_' property is invalid anyway. 25fd0200ef changed
how WSRs are written into snapshot (instead of writing WSRs we are
simply writing SMI CIDs) which broke previous logic.
* When building ProgramInfoNode for a Class node accommodate for the
existence of classes which don't have 'library_' property (e.g. base
objects like void and dynamic). Additionally, adjust how these base
objects are written into the snapshot profile so that we preserve
their names.
* Tweak tests diff and diff-collapse tests to pass, they were failing
because prologue removal compiler change made some of the diffs so
tiny that they are ignored by threshold filtering.
* Add two more tests: one that verifies that tracings flags don't have
any impact on the snapshot size and one that checks we correct
attribute instructions size to the function node from which these
instructions originated. This last test is added in anticipation of
Code object removal to make sure that vm_snapshot_analysis continues
to work correctly.
* Adjust sorting rules for Code cluster to make it more stable between
slightly different programs to stabilize output of
--print-instructions-sizes-to (depends on the sorting algorithm used
in libc, the test was failing on Mac but not on Linux).
These fixes should unblock relanding of b6dc4dad4dFixes#44507Fixesflutter/flutter#76313
TEST=pkg/vm_snapshot_analysis/test/instruction_sizes_test.dart
Cq-Include-Trybots: luci.dart.try:pkg-linux-release-try,pkg-win-release-try,pkg-mac-release-try
Change-Id: Iee0221dd3a507cb4f36d530404693ebfab3b7bf2
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/185826
Commit-Queue: Vyacheslav Egorov <vegorov@google.com>
Reviewed-by: Alexander Markov <alexmarkov@google.com>
This CL addresses two problems, which only reveal themselves when
analysing snapshots produced when function dropping is enabled.
When tests for snapshot analysis were written functions were dropped
in PRODUCT build by default - by currently this functionality needs
to be enabled separately or is automatically enabled when DWARF stack
traces are enabled. This CL changes test suite to enable DWARF stack
traces.
* When constructing ProgramInfo from V8 snapshot profile we should
not assume that Function nodes have any fields outside of owner_,
because Function node might be artificial and thus have no real
fields except for owner link.
* When writing V8 snapshot profile we should take care not to call
CreateArtificalNodeIfNeeded inside TraceStartWritingObject scope,
because CreateArtificalNodeIfNeeded might itself call
TraceStartWritingObject and these calls don't nest, the second one
overwrites the first one.
R=sstrickl@google.com
Bug: b/167601345
Change-Id: I40879ee087c38992388776af58b81bbefd147631
Cq-Include-Trybots: luci.dart.try:pkg-linux-release-try,pkg-win-release-try,pkg-mac-release-try
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/161703
Reviewed-by: Tess Strickland <sstrickl@google.com>
Commit-Queue: Vyacheslav Egorov <vegorov@google.com>
This CL adds --trace-precompiler-to option which generates a machine readable
precompiler trace (list of all compiled functions and their dependencies).
It also expands package:vm_snapshot_analysis with tools for reading and
analysing this trace.
For example snapshot_analysis explain dynamic-calls command allows
to list all dynamic calls sorted by their impact on the size of the AOT
snapshot.
Issue https://github.com/dart-lang/sdk/issues/41249
Cq-Include-Trybots: luci.dart.try:pkg-linux-debug-try,pkg-linux-release-try,pkg-win-release-try,pkg-mac-release-try
Change-Id: Ie49143f4da375067991991e2ad20a41ec67bb1c3
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/152851
Commit-Queue: Vyacheslav Egorov <vegorov@google.com>
Reviewed-by: Martin Kustermann <kustermann@google.com>
Vyacheslav Egorov